This article explores the legal framework and social attitudes towards cousin marriages in Japan, as well as the potential benefits and disadvantages of allowing such unions. It is illegal for first cousins to marry each other, but second cousins may still be able do so without breaking any laws. Public opinion on this matter varies greatly depending on who you ask, with some viewing it as an outdated practice and others seeing it as a way of preserving family ties. Benefits of allowing cousin marriage include keeping property within families, preserving cultural traditions and values, and reducing population growth. Potential disadvantages include genetic abnormalities or birth defects, increased levels of poverty, and social stigma or ridicule.